1. Technical Field
The present invention relates to an electrostatic charge image developing toner, an electrostatic charge image developer, a toner cartridge, a process cartridge, a method of producing an electrostatic charge image developing toner, and an image forming apparatus.
2. Related Art
Methods of visualizing image information via an electrostatic charge image, such as electrophotography, are used in various fields. In the electrophotography, an electrostatic charge image is formed on a photoreceptor through charging and exposing processes, the electrostatic charge image is developed with a developer including an electrostatic charge image developing toner (hereinafter, also simply referred to as “toner”), and the electrostatic charge image is visualized through transfer and fixing processes.
An example of the method of producing the toner is an emulsion aggregating method which is a wet production method, in which toner particles are produced from a mixture dispersion in which a binder resin, a colorant, and the like are dispersed through an aggregation process and the like. The toner produced through the use of the wet production method is smooth in toner shape and is superior in developability and transferability.
The wet production method toner is roughly classified into a production method using a styrene-acryl copolymer resin and a production method using a polyester resin. The styrene-acryl copolymer resin is mainly used for a monochromatic toner requiring a high molecular weight to lower an image surface gloss, because it can be easily polymerized. The polyester resin is mainly used for a color toner, because it can raise the image surface gloss due to the sharp melting property of the resin itself.
Recently, it has been considered that the polyester resin having a high sharp melting property should be used in a monochromatic printer in response to requirement for saving energy. However, since the polyester resin lowers the image surface gloss, there is a problem in that the increase in molecular weight of the resin markedly deteriorates the solubility in an organic solvent and it is thus difficult to produce the toner through the use of the wet production method.
When the polyester resin is crosslinked with the metallic ions, a chelating agent is added thereto to control the toner particle size or the degree of crosslinking.